Drafting mechanism for textile spinning machines



Jan. 8, 1963 K. EBERLE 3,071,824

DRAFTING MECHNISM FOR TEXTILE SPINNING MACHINES Filed April 20, 1959INVENTOR. Ko/vR/w 55ML:

f ATTORNEY Patented Jan. 8, 1963 3,071,824 DRAFTING MECHANISM FORTEXTILE SPINNING MACHINES Konrad Eberle, Flums, Switzerland Filed Apr.20, 1959, Ser. No. 807,358 Claims priority, application Switzerland Apr.21, 1958 1 Claim. (Cl. 19-258) The present invent-ion relates todrafting mechanisms for textile spinning machines.

Spinning machines with drafting or grooved rollers which haveasymmetrically profiled grooves are already known, but with theserollers a bottom belt of the machine has been looped about the relevantroller and the asymmetrical profile has been provided for the purpose ofimproving the entrainment of a top roller bearing against the belt.Moreover, it has already been proposed to .provide asymmetricallyprofiled grooving on drafting rollers which each co-.operate with asliding weighting member adapted in shape thereto.

According to the present invention there is provided a `drafting roller,wh-ich is arranged in a drafting zone and is in contact with the fibrousmaterial, with -grooving orientated in a direction opposite to thedirection of action of the drafting force. In this way, the material isbetter held back than by the conventional arrangements.

An embodiment of the invention will be explained with reference to theaccompanying drawings in which:

FIG. 1 illustrates a drafting zone of a drafting mechanisrn, and

IFIG. 2 is a view on a larger scale, `of the groot/ing of a deliveryroller in the drafting zone illustrated in F-IG. 1.

FIGURE l illustrates adrafting zone which is bounded by the nips betweena rapidly rotating pair of draft-ing rollers 1, 2 and a slowly rotatingpair of drafting rollers 3, l4. l'The lower drafting rollers 2 and 4 areprovided with asymmetric grooving.

iT he nip between the rollers 41 and 2 is shown on a larger scale inFIG. 2. f'llwo radii S and S extending from the centre of the roller 2are drawn through bottom corners 5 40 and 6, respectively, of anindividual groove or flute 7. The adjoining Walls of the groove 7 areinclined at angles a and with respect to the radii S and S',respectively. The angle a is greater than ,8, i.e. the rear wall 9 issubstantially radial whereas the forward wall 8 is inclined forwardlywith respect to the direction of circumferential movement of the rollers2. The result is that the grooving is forwardly inclined or orientatedin the direction of rotation of the roller. Since the rollers 1 and 2rotate faster than the rollers 3 and 4, the rather steep rear Walls 9 ofthe flutes produce a relatively firm grip on the fibrous materialwhereas the inclined forward walls 8 of the flutes afford a smoothrelease or disengagement of the material from the grooves 7. In the caseof the entry or feed roller 4, the fluting must, as shown in FIG. 1, beorientated in the direction opposite to the direction of rotation, inorder that it will be in opposition to the direction of action of thedrafting force in the drafting zone.

What is claimed is:

In a textile drafting arrangement, a forward drafting roller, a rearward`drafting roller spaced from said forward drafting roller, and apressure roller cooperating with each of said drafting rollers to formtwo spaced nips of a drafting zone, said drafting rollers being axiallyiluted, the flutes of the forward drafting roller having a rear wallwith respect to the direction of the circumferential movement of the-utes, said rear wall being substantially radial, the flutes of theforward drafting roller having a forward wall which is forwardlyinclined with respect to Ithe direction of the circumferential movementof the flutes, the flutes of the rearward drafting roller having aforward wall with respect to the direction of the circumferentialmovement of the flutes, said forward wall being substantially radial,the flutes of the rearward drafting roller having a rear Wall which -isrearwardly inclined with respect to the circumferential movement of theflutes.

References Cited in the tile of this patent UNITED STATES PATENTS

